Ash reduction of petroleum fractions



Aug. 29, 1961 c. w. BELL 2,998,383

ASH REDUCTION OF PETROLEUM FRACTIONS Filed Oct. 27, 1958 HEAVY HYDROCARBON INCORPORATOR PREHEATER -40 4i WATER SPENT SOLUTION SEPARATION ZONE INVENTOR.

CLIFFORD W. BELL,

ATTORNEY United States PatentO 2,998,383 ASH REDUCTION OF PETROLEUM FRACTIONS Clifiord W. Bell, Baytown, Tex., assignor, by mesne assignments, to Essa Research and Engineering Company, Elizabeth, N.J., a corporation of Delaware Filed Oct. 27, 1958, Ser. No. 769,723 4 Claims. (Cl. 208-251) This invention relates to a method for the removal of ash from heavy petroleum hydrocarbons. More particularly, this invention relates to a simple and inexpensive method for the removal ,of ash-from heavy petroleum hydrocarbons.

Petroleum hydrocarbon fractions which contain components boiling above about 950 R, such aspetroleum crude oil residuum fractions, heavy gas oil fractions, deasphalted oil fractions, etc. normally contain significant quantities of ash components. The ash components, in turn, are normally characterized by the presence therein of metals such as nickel, vanadium, iron, etc. Ash components adversely affect the susceptibility of the heavy fraction to improvement by catalytic treatment such as catalytic cracking, etc. It is therefore desirable to remove ash components from heavy petroleum hydrocarbon fractions.

However, the removal of ash constituents presents a serious problem inasmuch as expensive treating processes are generally not economically feasible due to the comparatively low economic value of the hydrocarbons. Thus, it is not desirable to use expensive reagents. Furthermore, with respect to treating agents that may be utilized, a serious economic disadvantage is encountered if significant quantities of the treating agent are lost to the treating process by solubilization in the hydrocarbon oil being treated, by the need for discard, etc.

In accordance with the present invention, however, a simple and inexpensive treating process is provided for significantly reducing the ash content of heavy petroleum hydrocarbons.

In accordance with the present invention, a heavy petroleum hydrocarbon is treated at a temperature within the range of about 50 to about 210 F. with from about 5 to 35 volume percent, based on the hydrocarbon charge, of an aqueous solution containing from about 5 percent to about 20 percent by volume of phenol.

The invention will be further illustrated by the accompanying drawing wherein the single figure is a schematic flow sheet illustrating a preferred embodiment of the present invention.

Turning now to the drawing, there is shown a source of a heavy hydrocarbon feed stock such as a storage tank 10. The heavy feed stock may be a gas oil fraction, a crude oil residuum fraction, a deasphalted oil fraction, etc. Normally, the heavy fraction will contain at least about 5 volume percent of components boiling above about 950 F.

' The feed stock is withdrawn from the storage tank by a line 12 controlled by a valve 14 leading to a preheater 16 wherein the temperature of .the feed stock may be adjusted to the desired treating temperature, if necessary. From the preheater 16, the hydrocarbon is charged by a line 18 to a suitable incorporating device such as a batfie plate incorporator. Simultaneously, phenol from a suitable source such as storage tank 22 is charged by way of a line 24 controlled by a valve 26 leading to a premixer 28 such as a bafile plate incorporator. Water from any suitable source (not shown) is charged to the premixer by way of a line 30 controlled by a valve 32 in an amount sufiicient to provide for an aqueous solution of phenol containing from about 5 to 20 percent of phenol. The resultant solution is discharged from the prcmixer by way of a line 2 which may contain, if necesamass Patented Aug. 29, 1961 sary, -a preheater 26 for adjustment of temperature. From the preheater 26 the solution is discharged by way of a line 38 leading to the incorporator 20.

Within the incorporator 20 the hydrocarbon feed stock is brought into intimate contact with the aqueous solution of phenol whereby a significant quantity of the ash components are removed from'the hydrocarbon feed stock.

The mixture is discharged from the incorporator 20 by way of a line 40 leading to a suitable separation zone 42 such asa settler wherein the mixture separates into a lower aqueous phase and a supernatant oil phase. The, oil phase, consisting of at least partially deashed oil, is discharged by way of a discharge line 44 for further processing, if deisred, and the spent treating solution is discharged by way of a line 46.

The spent-treating solution may be discarded from the system or, more preferably, may be treated for the at least partial recovery of the phenol contained therein by any suitable means such as distillation, etc. (not shown). In this ,way, a build-up of ash in the solution is prevented while maximum economy in the use of phenol is obtained.

Numerous advantages are obtained in accordance with the process of the present invention. Thus, as indicated, the feed stock is at least partially deashed. In addition, only a minor amount of the phenol and water are dissolved in the hydrocarbon feed stock. This is desirable in that the presence of large quantities of water in hydrocarbon feed stocks is generally undesirable and in that the phenol dissolved in the feed stock represents an economic loss.

The invention will be further illustrated by the following specific examples which are given by way of illustration and not as limitations on the scope of this invention.

Example I A petroleum hydrocarbon feed stock containing about 32 percent of a petroleum crude oil residuum fraction boiling below about 650 F., about 38 percent of naphtha bottoms, and about 29 volume percent of a sludge oil was prepared. The treated naphtha bottoms was a distillate residue obtained by distillation of a naphtha obtained by thermal cracking. The feed stock had a gravity of about 19.4 API, a viscosity at 210 of 66 SSU, and contained a total of about 0.21 weight percent ash of which about 0.18 weight percent represented water soluble ash.

The hydrocarbon feed stock was treated with about 20 volume percent of an aqueous solution of phenol containing about 10 volume percent of phenol at a treating temperature of about F. and a settling temperature of about 1-80 F.

After settling, an oil phase and a aqueous phase were obtained. The aqueous phase contained substantially all of the water initially mixed with the hydrocarbon feed stock.

The hydrocarbon material, after treatment, was found to contain a total of about 0.019 weight percent of ash, of which about 0.012 weight percent represented water soluble ash. No water was recovered on distillation of the product. The product was found to contain about 1.5 volume percent of phenol. The spent treating solution was found to contain about 2.7 volume percent of phenol.

Example 11 There was utilized for this experiment a deasphalted oil feed stock which contained about 13 parts per million (ppm) of nickel, about 24 ppm. of vanadium, and about 4 ppm. of iron. The feed stock was treated with varying quantities of aqueous solutions of phenol containing varying quantities of petrol. The phenolic solutions employed, the extent of treatment employed, and the results obtained are set forth in the following table.

From the table it will be observed that the best results were obtained by conducting the treating process in accordance with the present invention. Thus, it will be observed that the metals content of the product was minimized in accordance with the present invention, whereas the use of larger quantities of phenol resulted in a less efiicient metals removal process This was likewise the case when larger quantities of the aqueous phenolic treating solution were employed.

Having described my invention, what is claimed is:

l. A method for the treatment of an ash-containing heavy petroleum hydrocarbon feed stock containing at least about 5 volume percent of components boiling above 950 P. which comprises the steps of intimately contacting the feed stock with from about 5 to volume percent of an aqueous solution of phenol containing from about 5 to 20 volume percent of phenol, separating the treated mixture into an oil phase and a water phase substantially free of said hydrocarbon feed stock, and recovering said oil phase whereby an at least partially deashed oil is obtained said deashed oil phase comprising substantially all of said hydrocarbon feed stock.

2. A method as in claim 1 wherein the treatment is conducted at a temperature within the range of about to about 210 F.

3. A method as in claim 1 wherein the feed stock comprises a petroleum crude oil residuum fraction.

' 4. A method as in claim 1 wherein the feed stock comprises a deasphalted oil fraction.

References Cited in the file of this patent UNITED STATES PATENTS Reymond Nov. 4, 1958 

1. A METHOD FOR THE TREATMENT OF AN ASH-CONTAINING HEAVY PETROLEUM HYDROCARBON FEED STOCK CONTAINING AT LEAST ABOUT 5 VOLUME PERCENT OF COMPONENTS BOILING ABOVE 950*F. WHICH COMPRISES THE STEPS OF INTIMATELY CONTACTING THE FEED STOCK WITH FROM ABOUT 5 TO 35 VOLUME PERCENT OF AN AQUEOUS SOLUTION OF PHENOL CONTAINING FROM ABOUT 5 TO 20 VOLUME PERCENT OF PHENOL, SEPARATING THE TREATED MIXTURE INTO AN OIL PHASE AND A WATER PHASE SUBSTANTIALLY FREE OF SAID HYDROCARBON FEED STOCK, AND RECOVERING SAID OIL PHASE WHEREBY AN AT LEAST PARTIALLY DE- 